The semiconductor integrated circuit (IC) industry continues to improve the integration density of various electronic components (e.g., transistors, diodes, resistors, capacitors, etc.) by continual reductions in minimum feature size, which allow more components to be integrated into a given area. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. However, these advances have increased the complexity of processing and manufacturing ICs.
In the course of IC evolution, functional density (i.e., the number of interconnected devices per chip area) has generally increased while geometry size (i.e., the smallest component (or line) that can be created using a fabrication process) has decreased. This scaling down process generally provides benefits by increasing production efficiency and lowering associated costs.
During the scaling trend, various materials have been implemented for the gate electrode and the gate dielectric of semiconductor devices such as complementary metal-oxide-semiconductor (CMOS) devices. However, there are many challenges related to IC processing and manufacturing.